SF 



Issued August 18, 1909. 

U. S, DEPARTMENT OF AGRICULTURE, 

BUREAU OF ANIMAL INDUSTRY— Bulletin 116. 

A. D. MELVIN, Chief of Bureau. 



TESTS CONCERNING TUBERCLE BACILLI 
IN THE CIRCULATING BLOOD. 



BY 



E. C. SCHROEDER, M. D. V., 

Superintendent of Experiment Station, 
AND 

W. E. COTTON, 

Expert Assistant at Experimetit Station. 




WASHINGTON: 

GOVERNMENT PRINTING OFFICE. 

1909. 




Qass g -Ffi Cfe 

Book S'?'^ — 



Issued August 18, 190a. 



U. S. DEPARTMENT OF AGRICULTURE, 

BUREAU OF ANIMAL INDUSTRY.— Bullhtin 116. 

A. D. MF.I.VIN, Chief of Bl'rf.al'. 



TESTS CONCERNING TUBERCLE BACILLI 
IN THE CIRCULATING BLOOD. 



/■v 



■V^ 



y 



y' 



BY 



Ei^^CrSCHROEDER, M. D. V., 

Superintendent of Experiment Sfatioti, 
AND 

W. E. COTTON. 

I 

Expert Assistant at Experiment Station. 




WASHINGTON: 
GOVERNMENT PRINTING OFFICE. 

1909. 

-.1 






THE BUREAU OF ANIMAL INDUSTRY. 



Chief: A. D. Melvin. 
Assistant Chief: A. M. Farrington. 
Chief Clerk: Charles C. Carroll. 
Biochemic Division: M. Dorset, chief. 
Dairy Division: B. H. Rawl. chief. 

Inspection Division: Rice P. Steddom, chief; Morris Wooden, R. A. Ramsay, 
and Albert E. Behnke, associate chiefs. 
Pathological Division: John R. Mohler, chief. 
Quarantine Division: Richard W. Hickman, chief. 
Zoological Division: B. H. Ransom, chief. 
Experiment Station: E. C. Schroeder, siiperintentlent. 
Animal Husbandman: George M. Rommel. 
Editor: James M. Pickens. 
2 



B.6F D. 



LETTER OF TRANSMITTAL. 



U. S. Department of Agriculture, 

Bureau of Animal Industry, 
Washington^ D. C.^ July 7, 1909. 
Sir: I have the honor lO transmit herewith, and to recommend 
for publication in the bulletin series of this Bureau, the accompany- 
ing manuscript, entitled "Tests Concerning Tubercle Bacilli in the 
Circulating Blood," by Dr. E. C. Schroeder and Mr. W. E. Cotton, 
of the Experiment Station of this Bureau. 

The tests described in the bulletin were undertaken upon the 
appearance of a recent paper in which were recorded a large number 
of microscopic examinations of the blood of tuberculous individuals, 
the result of which, it was stated, proved that tuberculosis in all its 
forms was a bacteriemia. 

This conclusion was entirely contrary to the views of the authors 
of this bulletin, based upon their work in the Bureau for a long series 
of years ; and as the matter was of great importance in its bearing on 
the tuberculosis question, it was considered advisable to put it to a 
thorough test. Accordingly inoculation experiments were made with 
the blood of a large number of tuberculous cattle, and the results 
have demonstrated that tuberculosis is not in any sense a bacteriemia, 
and that if tubercle bacilli ever float in the blood of tuberculous 
animals this is an exceedingly rare condition. 
Respectfully, 

A. D. Melvin, 
Chief of Bureau. 
Hon. James Wilson, 

Secretary of Agnculture. 

3 



CONTENTS. 



Page 

Introduction 7 

Summary of present testa 9 

Records of cattle and results of .truinea-piti inoculations 10 

Discussion of results 18 

Supplemental tests regarding possible immunity 20 

Conclusions 23 

5 



TESTS CONCERNING TUBERCLE BACILLI IN THE CIR' 
CULATING BLOOD. 



INTRODUCTION. 

In a paper dealing with the occurrence of tubercle Ijacilli in the 
circulating blood, read before a medical societ}^ some months since 
and soon afterwards published in a medical journal," there were re- 
corded the results of microscopic examinations of the blood of 125 
tuberculous individuals, some of whom were affected with only 
incipient tuberculosis, and the statement was made that tubercle 
bacilli were found in the blood of every one of them. In some cases 
only a few bacilli were seen, but " they were mostly in large num- 
bers, and clumps of 30 to 40 bacilli were not unusual, especially in 
cases of acute miliary tuberculosis." From his observations the 
author of that paper formulated the conclusion : " It appears that 
tuberculosis in all its forms is a bacteriemia." 

That tubercle bacilli occasionally float in the blood stream is hardly 
open to question, because of the occurrence of isolated lesions in the 
bodies of otherwise tuberculous as well as otherwise healthy indi- 
viduals located in regions remote from the various channels that com- 
municate with the exterior. The same is true when we consider cases 
of more or less generalized tuberculosis with many lesions in widely 
separated portions of the body and cases of miliary tuberculosis with 
innumerable lesions of approximately, if not precisely, the same age 
and stage of development. But such occasional presence of tubercle 
bacilli in the circulating blood is a very different condition from their 
constant occurrence in it in sufficient numbers to justify the classifi- 
cation of tuberculosis as a bacteriemia. Hence, Rosenberger's con- 
clusion was received with considerable surprise and doubt. 

Although the conclusion seemed sufficientl}^ incredible because of 
the simple fact that a constant occurrence of tubercle bacilli in the 
blood of all tuberculous individuals could hardly have been over- 
looked by the host of investigators who have studied tuberculosis 

« Rosenberger. Rnndle C, "The presence of tubercle bacilli in the circulnting 
blood in tuberculosis." (Read before the Pathological Society of Philadelphia, 
December 10, 1908.) American Journal of the Medical Sciences, vol. 137, No. 
2, pp. 267-269. Philadelphia and New York, February, 1909. 



8 TESTS CONCERNING TUBERCLE BACILLI IN THE BLOOD. 

with no greatly different tedmiqne than Rosenberger nsed, we did not 
feel warranted in opposing it without offering some specific evidence. 
Because of the important bearing of the matter on the tuberculosis 
problem, the experiments hereinafter reported were carried out. 

Rosenberger stated that he found tubercle bacilli on microscopic 
examination in the blood of every one of the 125 cases of tuberculosis 
he studied, notwithstanding that some of the cases were incipient and 
failed to show tubercle bacilli in the sputum. It was, therefore, 
almost taken for granted that the microscopic examination of blood, 
according to his method, of animals affected with advanced and long 
standing tuberculosis and animals that were expelling tubercle bacilli 
from their bodies in large numbers would reveal at least a few 
tubercle bacilli. A considerable number of such microscopic examina- 
tions were made, but not a tubercle bacillus was found in our blood 
preparations, and hence we have to record wholly negative results 
with the blood of tuberculous animals. Similar negative results were 
obtained with the blood of tuberculous jjersons in two large New York 
hospitals." 

It is not uncommon for virulent tubercle bacilli to be present in 
animal substances in numbers too small to serve for their detection by 
optical methods. For example, at the Experiment Station we found 
the intraabdominal injection of guinea pigs with suspected milk to 
be a test for tubercle bacilli that has fully fifty times the delicacy of 
a microscopic examination. Furthermore, tinctoral and optical meth- 
ods of distinguishing between tubercle bacilli and other acid-fast 
bacteria are not wholly satisfactory, hence w^e concluded to inject a 
sufficient number of guinea pigs with blood from a sufficient number 
of certainly tuberculous cattle to show conclusiveh' that tubercle 
bacilli either are or are not commonly present in such blood. 

Incidently it appears that Doctor Rosenberger failed to confirm 
adequately by animal experiments his surprising microscopic observa- 
tions, which, if correct, would have been of the greatest value alone for 
the early and certain diagnosis of tuberculosis. In all he inoculated 
only two guinea pigs, of which he gives a record ; one with blood 
from a tuberculous person Avho was expelling tubercle bacilli per 
rectum, and one with blood from a case of acute miliary tuberculosis. 
The development of tuberculosis in the latter guinea pig can not 
be regarded as a remarkable phenomenon. There is nothing about 
the fact that a guinea pig contracted tuberculosis after an injection 
of blood obtained from a case of acute miliary tuberculosis that 
necessitates a modification of our currently accepted views on the 
presence of tubercle bacilli in the circulating blood. That is to say, 
we need not look upon tuberculosis as a bacteriemia because tubercle 

"Editorial in tlie Medicn! Itecord, New Yorlc. April 3. 1909. i). 5GS. 



CONDITION OF CATTLE USED IN TESTS. 9 

bacilli were demonstrated in blood of a kind in whicli Ave have long 
considered that they might sometimes occur. 

This leaves one guinea j^ig that may have some evidential value, 
but we must not lose sight of the fact that it was injected with 
blood obtained from a person who was expelling tubercle bacilli from 
his body and hence to some extent infecting his environment. We 
must also bear in mind that guinea pigs are highly susceptible to 
tubercle bacilli injected into their bodies, and that it is often impos- 
sible for an investigator who handles much tuberculous material, 
who is in frequent contact with tuberculous persons, and whose envi- 
ronment may be characterized as containing tubercle bacilli, to elimi- 
nate all danger of extraneous tuberculous infection sufficiently to 
make a test satisfactory when he seeks to verify the tuberculous 
character of some material from a tuberculous individual by the 
injection of one, and only one, guinea pig. 

SUMMARY OF PRESENT TESTS. 

Our own tests were made entirely with the blood of tuberculous 
cattle. In every case the blood was drawn from the jugular vein of 
the tuberculous animal and injected in its fresh, naturally warm 
state into the peritoneal cavity of a guinea pig. The tuberculous 
cattle, as their records show, may be divided into four distinct lots, 
according to their tuberculous condition : 

Lot 1. Four cattle, the precise tuberculous condition of which is 
known, because they were killed and examined jDOst-mortem shortly 
after blood was drawn from them for guinea-pig injections. 

Lot 2. Six cattle, known to be tuberculous because they had re- 
acted with tuberculin, because tubercle bacilli were found in their 
feces on microscopic examination, and because their feces were proven 
to be infectious by animal experiments. 

Lot 3. Nineteen cattle, known to be tuberculous because they had 
reacted with tuberculin and because tubercle bacilli were found in 
their feces on microscopic examination. 

Lot 4. Thirteen cattle, known to be tuberculous because they had 
reacted with tuberculin. 

We made no attempt to treat the blood used for the injections in 
any way, because we assumed that the best results Avould be obtained 
with it by transferring it as rapidly as possible from the tuberculous 
cattle to the peritoneal cavities of the guinea pigs. It was learned 
from the injections that guinea pigs tolerate a relatively large quan- 
tity of bovine blood in their peritoneal cavity. The guinea pigs that 
died shortly after as the result of the blood injections (about 15 per 
cent of all injected) with few exceptions showed extreme impaction 
and some inflammation of the large bowel, associated in several 
instances with invagination of the colon. 
2279— Bull. 116—09 2 



10 TESTS COXCERNi:XG TUBERCLE BACILLI IN THE BLOOD. 

The possibility exists that the intraperitoneal injection of from 
3 to 5 cubic centimeters of fresh, warm blood from tuberculous cattle 
induces an immunity in guinea pigs to the tubercle bacilli the blood 
may contain. Though this view is purely hypothetical and we know 
of nothing to sustain it, we haye carried out an investigation to prove 
or disi^rove it, and Avill give the results later in this paper. 

The total number of cattle from which blood injections were made 
was 42, and these, as their records show, represent a considerable 
variety relative to the severity and extent of the tuberculous disease 
with which they were affected. They ranged from animals that 
would not have been suspected to be diseased without a tuberculin 
test to a cow so badly affected that a calf of which she became the 
mother a little less than a year before her blood was used for guinea- 
pig injections was born affected with tjiberculosis contracted from 
ante-partum exposure to her tuberculous body. 

■ The total number of guinea pigs injected was 101. Of these, IG 
died within a few days after the injection and no doubt as a result of 
it. Three died of intercurrent affections, but not until a sufficient 
period of time had passed for lesions of tuberculosis to become 
clearly manifest. The remaining 85 lived until they were killed 
after a lapse of from seven and one-half to eleven weeks, or an 
average for all of seventy days after they were injected. The three 
guinea pigs that died of intercurrent affections showed no lesions of 
tuberculosis on post-mortem examination, and 84 of the 85 guinea 
pigs that lived imtil they were killed showed no lesions of any kind 
on autopsy. One guinea pig of the 85 showed lesions very slightly 
resembling tuberculosis, but these were proved by microscopic exami- 
nations and guinea-pig inoculation tests to be free from tubercle 
bacilli. 

A detailed record of the cattle and guinea pigs used in our tests 
follows : 

RECORDS OF CATTLE AND RESULTS OF GUINEA-PIG INOCULATIONS. 

The 42 cattle included in the records below are all that were avail- 
able for this investigation among the tuberculous cattle kept for 
various purposes at the Bureau of Animal Industry Experiment Sta- 
tion. The general condition of the cattle is briefly defined as good, 
fairly good, fair, or poor; and as these terms are used somewhat 
arbitrarily, it is desirable to specify more precisely what they are 
intended to convey. The word* " good " is used in connection with 
cattle that were really to all appearances in excellent physical condi- 
tion, and of which no one would suspect that they were diseased. 
The words " fairly good " are used to mean that condition commonly 
found among dairy cows of the better class. " Fair " is used to desig- 



RESULTS OF GUINEA-PIG IXOC'ULATIOXS. 11 

iiate a condition which the average dairyman regards as satisfactory, 
and " poor '' is applied to cattle that arc thin or that show visible 
symptoms of disease. 

LOT L 

Bull 393, jjeueral condition very good, had boon affected with tuberculosis a 
year or more; was Ivilled and examined post-mortem April 8, 1909. The autopsy 
revealed only one small tuberculous lesion located in one of the superficial 
inguinal glands. 

On February 5, 1909, two guinea pigs, Xos. 2S91 and 2892, received each an 
intraabdominal injection of 2 c. c. of blood from the bull. One guinea pig, 
No. 2891, died on February 14, 1909, affected with invagination of the bowel. 
The other guinea pig remained healthy until April 13, 1909 (sixty-seven days 
after injection), when it was killed and found on post-mortem examination to 
be free from lesions of disease. 

Cow 533, general condition poor, had been affected with tuberculosis two 
years or more; was killed and examined post-mortem April 24, 1909. The 
autopsy revealed the following conditions : The principal lobe of the light lung 
contained a cavity about 3 inches in diameter, partly filled with pasty, necrotic 
tuberculous material. This cavity was in direct communication with a large 
bronchial tube, which contained a considerable amount of material discharged 
from the cavity. Sprinkled throughout the lungs generally were a number of 
smaller tuberculous foci, in a completely broken-down condition. The medias- 
tinal and mesenteric lymph glands and the liver were sprinkled with tuberculous 
foci, some of which were as much as half an Inch in diameter. Prior to the 
cow's death her feces were examined microscopically on nine different days and 
on six of these days were found to contain tubercle bacilli. 

On February 3, 1909, two guinea pigs, Nos. 2859 and 2800, received each an 
intraabdominal injection of 3 c. c of blood of the cow. The guinea pigs re- 
mained healthy until April 13, 1909 (sixty -nine days after injection), when 
they were killed and found on post-mortem examination to be free from lesions 
of disease. 

Cow 549, general condition poor, had been affected with tuberculosis several 
years. On March 27, 1908, she gave birth to a calf affected with congenital 
tuberculosis. The cow was killed April 8, 1909, and on autopsy was found to 
be affected with advanced, generalized tuberculosis. The lungs contained 
lesions varying from quite recent tuberculous disease to large tuberculous 
cavities that had discharged most of their contents through the bronchial tubes. 
No tests were made relative to the infectious character of the feces before death. 

On February 3, 1909, two guinea pigs, Nos. 2863 and 2864, rec-eived each an 
intraabdominal injection of 3 c. c. of blood from the cow. The guinea pigs were 
killed April 13, 1909 (sixty-nine days after injection), and on post-mortem 
examination were found to be free from lesions of disease. 

Cow 5.52, general condition poor, had been affected with tuberculosis several 
years: was killed April 1. 1909. The autopsy revealed a fairly generalized 
tuberculosis with lesions of greater or less magnitude in the lungs and in the 
pharyngeal, bronchial, and mesenteric lymph glands. Trior to the cow's death 
her feces were examined microscopically on ten different days and on six of 
these days were found to contain tubercle bacilli. 

Hogs that were fed feces from the cow contracted tuberculosis, and guinea pigs 
inoculated subcutaneously with small masses of her feces likewise contracted 
tuberculosis. 



12 TESTS CONCERNING TUBERCLE BACILLI IN THE BLOOD. 

Guinea pigs were injected intraabdominally with blood from tliis cow as 
follows : 

January 25, 1909, guinea pig 2785 received 5 c. c. 

January 25, 1909, guinea pig 2786 received 5 c. c. 

January 25, 1909, guinea pig 2783 received 2^ c. c. 

January 25, 1909, guinea pig 2784 received 2A c. c. 

January 2.5, 1909, guinea pig 2781 received 1 c. c. 

January 25, 1909, guinea pig 2782 received 1 c. c. 

February 3, 1909, guinea pig 2861 received 3 c. c. 

February 3, 1909, guinea pig 2862 received 3 c. c. 

February 5. 1900, guinea pig 2889 received 2i c. c. 

February 5, 1909, guinea pig 2890 received 2h c. c. 
Guinea pigs 2786 and 2890 died prematurely as a I'esult of the blood injections, 
and the remaining 8 were killed on the following dates and on autopsy were 
found to be free from lesions of disease: Guinea pigs 2781 and 2782, killed 
March 27, 1909 (sixty-one days after injection) ; guinea pigs 2783 and 2784, 
killed April 13, 1909 (seventy-eight days after injection) ; guinea pig 2785, 
killed April 12, 1909 (seventy-eight days after injection) ; guinea pig 2889, 
killed April 13, 1909 (sixty-seven days after injection) ; guinea pigs 2861 and 
2862, killed April 13, 1909 (sixty-nine days after injection). 

LOT 2. 

Cow 511, general condition i)oor, had been affected with tuberculosis eighteen 
mon+hs or more. Microscopic examinations of the feces on seven different days 
revealed tubercle bacilli on three days. A hog fed with feces from the cow 
contracted tuberculosis. 

On February 1, 1909, two guinea pigs, Nos. 2829 and 2830, received each 
an intraabdominal injection of 3 c. e. of blood from the cow. The guinea pigs 
remained healthy until April 13, 1909 (seventy-one days after injection), when 
they were killed and found on autopsy to be free from lesions of disease. 

Cow 537, general condition fairly good, had been affected with tuberculosis 
more than two years. Microscopic examination of the feces on fifteen days 
revealed tubercle bacilli on eleven days. Guinea pigs inoculated with small 
masses of feces contracted tuberculosis. 

Guinea pigs were injected intraabdominally with blood from the cow as 
follows : 

February 4. 1909, guinea pig 2871 received 3 c. c. 
February 4, 1909, guinea i»ig 2872 received 3 c. c. 
February 19. 1909. guinea pig 3062 received 3 c. c. 
February 19, 1909, guinea pig 3063 received 3 c. c. 

Guinea pig 2872 died prematurely as a result of the injection. Guinea pig 
2871 was killed April 13, 1909 (sixty-eight days after injection), and on autopsy 
was found to be free from lesions of disease. Guinea pigs 3062 and 3063 were 
killed April 13, 1909 (fifty-three days after injection), and on autopsy were 
found to be free from lesions of disease. 

Cow 538, general condition very poor, had been affected with tuberculosis 
two years or longer. ^Microscopic examinations of feces on eleven different 
days revealed tubercle bacilli on nine days. Guinea pigs inoculated with 
small masses of feces and hogs fed feces of this cow contracted tuberculosis. 

On February 3, 1909, two guinea pigs, Nos. 2851 and 2852, received each an 
intraabdominal injection of 3 c. c. of blood from the cow. On April 13, 1909 
(sixty-nine days after injection), the guinea pigs were killed and on autopsy 
were found to be free from lesions of disease. 



RESULTS OF GUINEA-PIG INOCULATIONS. 13 

Cow 555, general coudition fairly good, had beeu affected with tuberculosis 
more than two years. Microscopic examinations of feces on five different days 
revealed tubercle bacilli on two days. A hog fed feces from the cow contracted 
tuberculosis. 

On January 30, 11)09, two guinea pigs, Nos. 2811 and 2812, received each an 
intraabdominal injection of 3 e. e. of blood from the cow. Guinea pig 2811 
died prematurely as a result of the injection. Guinea pig 2812 was killed 
xVpril 12, 1909 (seventy-two days after injection), and on post-mortem e.xanii- 
nation was found to be free from lesions of disease. 

Cow 5G7, general condition good, had been affected with tuberculosis at least 
two and one-half years. Microscopic e.xaminations of feces on ten different 
days revealed tubercle bacilli on five days. A hog fed with feces from the 
cow contracted tuberculosis. 

On February 4, 1909, two guinea pigs, Nos. 28G9 and 2870, received each an 
intraabdominal injection of 3 c. c. of blood from the cow. The guinea iiigs 
were liilled April 12, 1909 (sixty-seven days after injection), and on autopsy 
were found to be free from lesions of disease. 

Cow 646, general condition fair; had been affected with tuberculosis for some 
time, but just how long was not known. ^Microscopic examinations of feces on 
two different days revealed tubercle bacilli on one day. Guinea pigs inoculated 
with her feces contracted tuberculosis. 

On February 2, 1909, two guinea pigs, Xos. 2847 and 2848, received each an 
intraabdominal injection of 3 e. c. of blood from the cow. The guinea pigs 
were killed April 13, 1909 (seventy days after injection), and on autopsy were 
found to be free from lesions of disease. 

LOT :;. 

Cow 503, general condition good : had been affected with tuberculosis at least 
two and one-half years. Microscopic examinations of feces on two days revealed 
tubercle bacilli on one day. 

On January 30, 1909, two guinea pigs, Nos. 2805 and 2806, received each an 
intraabdominal injection of 3 c. c. of blood from the cow. The guinea pigs 
were killed April 30, 1909 (seventy-three days after injection), and on autopsy 
were found to be free from lesions of disease. 

Cow 510, general condition fairly good ; had been affected with tuberculosis 
about three years. Microscopic examinations of feces on three days revealed 
tubercle bacilli on two days. 

Guinea pigs were injected intraabdominally with blood from the cow as 
follows : 

January 29, 1909, guinea pig 2791, received 5 c. c. 
January 29, 1909, guinea pig 2792, received 5 c. c. 
February 4, 1909, guinea pig 2881, received 3 c. c. 
February 4, 1909, guinea pig 2882, received 3 c. c. 

Guinea pigs 2791 and 2792 died prematurely as a result of the injections. 
Guinea pigs 2881 and 2882 were killed April 13, 1909 (sixty-eight days after 
Injection), and on autopsy were found to be free from lesions of disease. 

Cow 512, general condition good : had been affected with tuberculosis eighteen 
months or longer. Microscopic examinations of feces on six different days 
revealed tubercle bacilli on four days. 

On February 11, 1909, two guinea pigs. Nos. 2823 and 2824, received each an 
intraabdominal injection of 3 c. c. of blood from the cow. The guinea pigs 
were killed April 12, 1909 (seventy days after injection), and on autopsy were 
found to be free from lesions of disease. 



14 TESTS CONCERNING TUBERCLE BACILLI IN THE BLOOD. 

Cow 513, general i-oudition fairly good, but had greatly enlarged throat 
glands; had been affected with tuberculosis eighteen months or longer. Micro- 
scopic examinations of feces on four different days revealed tubercle bacilli on 
two days. 

On February 2, 1909, two guinea pigs, Nos. 2835 and 2S36, received each an 
intraabdominal injection of 3 c. c. of blood from the cow. Guinea pig 2835 died 
prematurely as a result of the injection. Guinea pig 2s3G was killed April 12, 
1909 (sixty -nine days after injection), and on autopsy was found to be free 
from lesions of disease. 

Cow 514, general condition poor; had been affected with tuberculosis about 
three years. Microscopic examinations of feces on three different days revealed 
tubercle bacilli on one day. 

On January 30, 1909, two guinea pigs, Nos. 2815 and 2816, received each aii 
intraabdominal injection of 3 c. c. of blood from the cow. Guinea pig 2816 died 
of an intercurrent affection ]\Iarch 3, 1909 (thirty-two days after injection), and 
on autopsy was found to be free from lesions of tuberculosis. Guinea pig 2815 
was killed April 12, 1909 (seventy-two days after injection), and on autopsy 
was found to be free from lesions of disease. 

Cow 515, general condition fair, had been affected with tuberculosis eighteen 
months or longer. ^Microscopic examinations of feces on six different days 
revealed tubercle bacilli on four days. 

On February 1, 1909, two guinea pigs, Nos. 2821 and 2822, received each an 
intraabdominal injection of 3 c. c. of blood from the cow. The guinea pigs were 
killed April 12, 1909 (seventy days after injection), and on autopsy were found 
to be free from lesions of disease. 

Cow 516, general condition fairly good, had been affected with tuberculosis 
eighteen months or longer. Microscopic examinations of feces on seven different 
days revealed tubercle bacilli on four days. 

On February 1, 1909, two guinea pigs, Nos. 2831 and 2832, received each an 
intraabdominal injection of 3 c. c. of blood from the cow. The guinea pigs 
were killed April 13, 1909 (seventy-one days after injection), and on autopsy 
were found to be free from lesions of disease. 

Cow 536, general condition poor, had been affected with tuberculosis two years 
or longer. Microscopic examinations of feces on eleven different days revealed 
tubercle bacilli on eight days. 

On February 3, 1909, two guinea pigs, Nos. 2805 and 2866, received each an 
intraabdominal injection of 3 c. c. of blood from the cow. The guinea pigs 
were killed April 13, 1909 (sixty-nine days after injection), and on autopsy 
were found to be free from lesions of disease. 

Cow 551, general condition fairly good, had been affected with tuberculosis 
two years or longer. Microscopic examinations of feces on nine different days 
revealed tubercle bacilli on three days. 

On February 1, 1909, two guinea pigs, Nos. 2833 and 28.34, received each an 
inti'aabdoniinal injection of 3 c.,c. of blood from the cow. The guinea pigs were 
killed April 12, 1909 (seventy days after injection), and on autopsy were found 
to be free from lesions of disease. 

Cow 553, general condition fairly good, had been affected with tuberculosis 
two years or longer. ^Microscopic examinations of feces on three different days 
revealed tubercle bacilli every day. 

On February 1, 1909, two guinea pigs, Nos. 2827 and 2828, received each an 
intraabdominal injection of 3 c. c. of blood from the cow. The guinea pigs 
were killed April 13. 1909 (seventy-one days after injection), and on autopsy- 
were found to be free from lesions of disease. 



RESULTS OF GUINEA-PKi IXOC'ULATIONS. 15 

Cow G20, general condition good, had been affected with tuberculosis a year 
or longer. Microscopic examinations of feces on four different days revealeil 
tubercle bacilli on one day. 

On P^bruai-y .3, 1909, two guinea pigs, Nos. 2Sr)r) and 2S5G, received each an 
intraabdominal injection of 3 c. c. of blood from the cow. The guinea pigs 
were killed April 1^, 1909 (sixty-nine days after injection), and on autopsy 
were found to be free from lesions of disease. 

Cow G29, general condition fair, had been affected with tuberculosis at least 
one year. Microscopic examinations of feces on five different days revealed 
tubercle bacilli on two days. 

On February 3, 1909, two guinea pigs, Nos. 2857 and 2858, received each an 
intraabdominal injection of 3 c. c. of blood from the cow. The guinea pigs 
were killed April 13, 1909 (sixty-nine days after injection), and on autopsy 
were found to be free from lesions of disease. 

Cow 631, general condition fair, had been affected with tuberculosis at least 
one year. IMicroscopic examinations of feces on four different days revealed 
tubercle bacilli on one day. 

On February 4, 1909, two guinea pigs, Nos. 2877 and 2S7S, received each 
an intraabdominal injection of 3 c. c. of blood from the cow. The guinea pigs 
were killed April 13, 1909 (sixty-eight days after injection), and on autopsy 
were found to be free from lesions of disease. 

Bull 635, general condition good, had been aff'ec-ted with tuberculosis over 
two years. Microscopic examinations of feces on three different days revealed 
tubercle bacilli on one day. 

On January 20, 1909. two guinea pigs, Nos. 2817 and 2818, received each an 
intraabdominal injection of 3 c. c. of blood from the bull. Guinea pig 2818 
died prematurely as a result of the injection. Guinea pig 2817 was killed April 
12, 1909 (seventy-two days after injection), and on autopsy was found to be 
free from lesions of disease. 

Cow 636, general condition fairly good, had been affected with tuberculosis 
at least one year. Microscopic examinations of feces on five different days 
revealed tubercle bacilli on two days. 

On January 30, 1909, two guinea pigs, Nos. 2803 and 2804, received each an 
intraabdominal injection of 3 c. c. of blood from the cow. The guinea pigs 
were killed April 12, 1909 (seventy-two days after injection), and on autopsy 
■were found to be free from lesions of disease. 

Cow 638, general condition fairly good, had been affected with tuberculosis 
over two years. Microscopic examinations of feces on four different days 
revealed tubercle bacilli on all four days. 

Guinea pigs were given intraabdominal injections of the blood of this cow 
as follows : 

January 29, 1909, guinea pig 2795 received 5 c. c. 
January 29, 1909, guinea pig 2796 received 5 e. c. 
Februai-y 4, 1909, guinea pig 2879. received 3 c. c. 
February 4, 1909. guinea pig 2880 received 3 c. c. 

Guinea pig. 2795 died prematurely as a result of tlie injection. Guinea pig 
2796 was killed April 12, 1909 (seventy-three days after the injection), and on 
autopsy was found to be free from lesions of disease. Guinea pigs 2879 and 
2880 were killed April 12, 1909 (sixty-seven days after injection), and on 
autopsy were found to be free from lesions of disease. 

Cow 639, general condition good, had been affected with tuberculosis at least 
one year. Microscopic examinations of feces on four diff'erent days revealed 
tubercle bacilli on one day. 



16 TESTS CONCERNING TUBERCLE BACILLI IN THE BLOOD. 

Guinea pigs were given intraabdominal injections of tlie blood of this cow 
as follows : 

January 29, 1909, guinea pig 2801 received 5 c. c. 
January 29, 1909, guinea pig 2802 received 5 c. c. 
February 5, 1909, guinea pig 2887 received 3 c. c. 
February 5, 1909, guinea pig 2888 received 3 c. c. 
Guinea pig 2801 died prematurely as a result of the injection. Guinea pig 
2802 was killed April 12, 1909 (seventy-three days after injection), and on 
autopsy several small necrotic foci were found in the liver and sitleen. The 
lesions were not at all like the conditions caused by the tubercle bacillus, 
and microscopic examinations failed to reveal tubercle bacilli. Some of the 
abnormal tissue was used to make subinoculations into guinea pigs ; the sub- 
inoculated guinea pigs failed to show tuberculosis. 

Guinea pigs 2887 and 2888 were killed April 13, 1909 (sixty-seven days after 
the injection), and on autopsy were found to be free from lesions of disease. 

Cow 640, general condition good, had been affected with tuberculosis over 
two years. Microscopic examinations of feces on three different days revealed 
tubercle bacilli on all three days. 

On January 29, 1909, two guinea pigs, Nos. 2799 and 2800, received each an 
intraabdominal injection of 5 c. c. of blood from the cow. The guinea pigs 
were killed April 12 1909 (seventy-three days after injection), and on autopsy 
were found to be free from lesions of disease. 

Cow 642, general condition good, had been affected with tuberculosis at least 
one year. Microscopic examinations of feces on three different days revealed 
tubercle bacilli on two days. 

Guinea pigs were injected intraabdominally with blood from this cow as 
follows : 

January 29, 1909, guinea pig 2793 received 5 c. c. 
January 29, 1909, guinea pig 2794 received 5 c. c. 
February ,5, 1909, guinea pig 2885 received 3 c. c. 
February 5, 1909, guinea pig 2886 received 3 c. c. 
Guinea pig 2794 died prematurely as the result of the injection. Guinea pig 
2886 died March 5, 1909 (twenty-eight days after injection), of an intercurrent 
affection, and the autopsy revealed no lesions resembling tuberculosis. Guinea 
pig 2793 was killed April 13. 1909 (seventy-three days after injection), and on 
autopsy was found to be free from lesions of disease. Guinea pig 2885 was 
killed April 13, 1909 ( sixty-.seven days after injection), and on autopsy was 
found to be free from lesions of disease. 

LOT 4. 

Cow 479, general condition fair, but had greatly enlarged throat glands, had 
been affected with tuberculosis about three years. 

On February 4, 1909, two guinea pigs, Nos. 2873 and 2874, received each an 
intraabdominal injection of 3 c. c. of her blood. The guinea pigs were killed 
April 13, 1909 (sixty-eight days after injection), and on autopsy were found to 
be free from lesions of disease. 

Bull 508, general condition good, had been affected with tuberculosis about 
two and one-half years. 

On February 4, 1909, two guinea pigs. Xos. 2867 and 2868, received each an 
intraabdominal injection of 3 c. c. of his blood. The guinea pigs were killed 
April 12, 1909 (sixty-seven days after injection), and on autopsy were found 
to be free from lesions of disease. 

Cow 517, general condition good, had been affected with tuberculosis about 
two and one-half years. 



RESULTS OF GUINEA-PIG INOCULATIONS, 17 

On Febniary 1, T.)(»!), Iwo Kiiiiioa i)lss, Nos. 2825 and 2826, received each an 
intraabdominal injection of 3 c. c. of lier blood. Guinea pig 2825 died of an 
intercurrent affection April 5, 1009 (sixty-three days after injection), and on 
autopsy was found to be free from lesions of tuberculosis. Guinea pi?; 2820 
was killed April 1.S, ]l>or> (seventy-one days after injection), and on autopsy 
was found to be free from lesions of disease. 

Cow 5()0, general condition fair, liad been affected with tuberculosis about 
two years. 

On February 1, 1909, two guinea pigs, ^:os. 2819 and 2820, received each an 
intraabdominal injection of 3 c. c. of her blood. The guinea pigs were lulled 
April 12. 1909 (seventy days after injection), and on autopsy were found to be 
free from lesions of disease. 

Cow G30, general condition fair, had been affected with tuberculosis about 
one year. 

On February 3, 1909, two guinea pigs, Nos. 2853 and 2854, received each an 
intraabdominal injection of 3 c. c. of her blood. The guinea pigs were killed 
April 13. 1909 (sixty-nine days after injection), and on autopsy were found to 
be free from lesions of disease. 

Cow G32, general condition good, had been affected with tuberculosis at least 
one year. 

On January 30, 1909, two guinea pigs, Nos. 2807 and 2808, received each an 
intraabdominal injection of 3 c. c. of her blood. Guinea pig 2808 died prema- 
turely as a result of the injection. Guinea pig 2807 was killed April 13, 1909 
(seventy-two days after injection), and on autopsy was found to be free from 
lesions of disease. 

Cow 6.33, general condition fair, had been affected with tuberculosis at least 
one year. 

On January 30, 1909, two guinea pigs. Nos. 2813 and 2814, received each an 
intraabdominal injection of 3 c. c. of her blood. Guinea pig 2813 died prema- 
turely as a result of the injection. Guinea pig 2814 was killed on April 12, 
1909 (seventy-one days after injection), and on autopsy was found to be free 
from lesions of disease. 

Cow 634, general condition fair, had been affected with tuberculosis at least 
one year. 

On January 29, 1909, two guinea pigs, Nos. 2787 and 2788, received each an 
intraabdominal injection of 3 c. c. of her blood. The guinea pigs were killed 
April 12, 1909 (seventy-three days after injection), and on autopsy were found 
to be free from lesions of disease. 

Cow 641, general condition fair, had been affected with tuberculosis over 
two years. 

On January 29. 1909, two guinea pigs. Nos. 2797 and 2798. received each an 
intraabdominal injection of 5 c. c. of the blood of the cow, and on February 
4, 1909, two guinea pigs, Nos. 2875 and 2876, received each a similar injection 
of 3 c. c. of blood. Guinea pig 2798 died prematurely as a result of the injec- 
tion. Guinea pig 2797 was killed April 12. 1909 (seventy-five days after in- 
jection), and guinea pigs 2875 and 2876 were killed April 12, 1909 (sixty- 
seven days after injection). The last three guinea pigs were found to be free 
from lesions of disease. 

Cow 644. general condition fair, had been affected with tuberculosis four 
months or more. 

On February 2, 1909, two guinea pigs. Nos. 2849 and 2850, received each an 
intraabdominal injection of 3 c. c. of blood of the cow. The guinea pigs were 
killed April 13, 1909 (seventy days after injection), and on autopsy were found 
to be free from lesions of disease. 



18 TESTS CONCEKNING TUBEKCLE BACILLI IN THE BLOOD. 

Cow 645, general condition good, had been affected with tuberculosis three 
months or more. 

On February 2, 1909, two guinea pigs, Nos. 2845 and 2846, received each an 
intraabdominal injection of 3 c. c. of her blood. Guinea pig 2845 died pre- 
maturely as a result of the injection. Guinea pig 2846 was killed April 13, 
1909 (seventy days after injection), and on autopsy was found to be free from 
lesions of disease. 

Cow 648. general condition good, had been affected with tuberculosis for an 
unknown period of time. She was brought to the Experiment Station shortly 
before her blood was used for guinea-pig injections, and reacted with tuber- 
culin. 

On February 2, 1909, two guinea pigs, Nos. 2837 and 2838, received each an 
intraabdominal injection of 3 c. c. of her blood. The guinea pigs were killed 
April 12, 1909 (sixty-nine days after injection), and on autopsy were found 
to be free from lesions of disease. 

Cow 657, general condition fair, had been affected with tuberculosis for an 
unknown period of time. She was brought to the Experiment Station shortly 
before her blood was used for guinea-pig injections, and reacted with tuber- 
culin. 

On February 2, 1909, two guinea pigs, Nos. 2841 and 2842, received each an 
intraabdominal Injection of 3 c. c. of her blood. The guinea pigs were killed 
April 12. 1909 (sixty-nine days after injection), and on autopsy were found 
to be free from lesions of disease. 

DISCUSSION OF RESULTS. 

Among the •l^ cattle enumerated above, 27, or G4| per cent, were 
shown by microscopic examinations to be discharging tubercle bacilli 
from their bowels — in most instances intermittently — and the infec- 
tious character of the feces in T cases, or 1G| per cent, was demon- 
strated by animal experiments — that is, feeding and inoculation tests. 

These two facts — that 27 of the cattle were shown by microscopic 
tests to be expelling tubercle bacilli per rectum, while only 7 were 
proved by animal experiments to be passing infected feces — must 
not be taken as being in any sense contradictory, as the feces of only 
a sufficient number of tuberculous cattle were tested by animal feeding 
and inoculation experiments to prove conclusively that the acid-fast 
bacilli found on microscopic examinations in the feces of tuberculous 
cattle are certainly live, virulent tubercle bacilli. 

Relative to the expulsion of tubercle bacilli from the bowels of 
tuberculous cattle, all the evidence we have indicates that the bacilli 
have their origin in the lung and throat, from which regions they 
are coughed up, swallowed, and passed through and out of the intes- 
tinal canal without appreciable loss of pathogenic virulence. That a 
large proportion of the tubercle bacilli swallowed by cattle really 
pass through their bodies and out per rectum without a determinable 
loss of virulence was experimentally shown in some of our earlier 
work.« We have absolutely no reason to believe that tubercle bacilli 

" Bureau of Animal Industry, Bulletins 88 and 99. 



DISCUSSION OF RESULTS. 19 

enter the intestinal canal from the lymph radicals or blood capil- 
laries or by any complex and mysterious system of transporta- 
tion from lesions of all descriptions and kinds in any or every 
portion of the body. It is our conviction that, unless an open tuber- 
culosis is in more or less direct communication with the intestinal 
canal or there is a tuberculous disease of the intestine itself, Avhich 
latter is rare among cattle, no tubercle bacilli will be expelled with 
the feces. 

If tuberculosis in all its forms Avas a bacteriemia the expulsion of 
tubercle bacilli from the bowels of all tuberculous individuals, as well 
as with their urine, saliva, milk, and other bodily secretions, would 
follow as a natural consequence. Those who have carefully studied 
the secretions from the uninvolved organs of tuberculous subjects 
know how rarely tubercle bacilli are detected in them even with the 
application of the most delicate tests. 

When we consider cattle like Nos. 533, 549, and 552 — three of 
the four animals of which autopsy records are given — and note that 
they were so badly diseased that thej^ Avould have been condemned on 
superficial examination as wholly unfit for use as food under the 
existing meat-inspection regulations, the absence of tubercle bacilli 
from their blood may be regarded as a sufficient reason for assuming 
that the possible occurrence of tubercle bacilli in the blood of tuber- 
culous animals will almost invariably be associated with pathological 
conditions of a very marked character, or that the tubercle bacilli will 
be present in extremely small numbers and will speedily be filtered 
out of the blood stream. Cow 533 had been afi^ected with tuberculosis 
two years or longer, was in poor condition as a result of the disease, 
and on autopsy was found to have an extensive, open tuberculosis of 
the lung and lesions of tuberculosis in the liver and in both the 
thoracic and abdominal lymph glands. Cow 549 was, if anj^thing, 
even more severely and extensively affected, and had given birth to a 
congenitally tuberculous calf less than a year before her blood was 
injected into guinea pigs. Cow 552 was also affected with general- 
ized, advanced, open tuberculosis, and prior to the use of her blood 
for the guinea-pig injections was found to be passing from her bowels 
large numbers of tubercle bacilli, which were proved by feeding tests 
to be virulent for hogs and by inoculation tests to be virulent for 
guinea pigs. With the blood obtained from these three cows 14 
guinea pigs were injected, of which 2 died prematurely and 12 lived 
two months or more afterwards, until they were intentionally killed, 
when they were found on post-morten examination to be wholly free 
from lesions of disease of any kind. 

The possibility exists that tubercle bacilli introduced into the 
stomach and intestine by swallowing may be taken up by the lymph 
radicals, passed along the lymph channels, and emptied through the 



20 TESTS CONCEELNING TUBEECLE BACILLI IN THE BLOOD. 

great lymph ducts into the venous circulation. The investigations 
of Xicolas and Descos, Eavenel, Calmette and Guerin, Schlossman 
and Engle, and others speak for this; but such tubercle bacilli will 
not be very numerous and will no doubt be filtered out of the blood 
as soon as it reaches the lung through the heart and pulmonary 
arteries, to which it passes directly after it has received the lymph 
stream. 

SUPPLEMENTAL TESTS REGARDING POSSIBLE IMMUNITY. 

We have already stated that the possibility exists that the intra- 
peritoneal injection of from 3 to 5 c. c. of fresh, warm blood from 
tuberculous cattle induces an immunity in guinea pigs to the tubercle 
bacilli the blood may contain. Although we knew of nothing to 
uphold this theory, we considered it necessary to undertake an investi- 
gation to prove or disprove it, the results of which are now presented. 

On April 24, 1900, blood and tuberculous material w^as obtained 
from cow 533 (see record of cow on p. 11) for a number of guinea- 
pig injections. The primary object of the injections was to prove 
that the blood of a tuberculous cow, when introduced into the peri- 
toneal cavity of a guinea pig, has no retarding influence on the devel- 
opment of tuberculosis from tubercle bacilli that may be present in it. 

Cow 533 was first bled from the jugular vein and then at once 
killed. As soon as she was dead a tuberculous mediastinal gland was 
removed from her body and 500 mg. of it emulsified with 2 c. c. of 
sterile, normal salt solution. Cover glasses of this emulsion, stained 
with carbolfuchsin and decolorized with 20 per cent sulphuric acid, 
revealed on microscopic examination, on an average, two tubercle 
bacilli each. The emulsion was mixed with an additional quantity of 
sterile, normal salt solution, so that each cubic centimeter of the 
dilution represented a streng-th equal to one drop of the original 
emulsion. 

The blood obtained from the cow prior to her death and the diluted 
emulsion made with the tuberculous mediastinal gland from her body 
were used to inject seven groups of guinea pigs, the records of which 
are given below. 

The guinea pigs in the seven different groups were injected for the 
following purposes: Group 1, to serve as checks on the absence or 
presence of tubercle bacilli in the blood of the tuberculous cow that 
was used for the investigation; group 2, to show that the intra- 
abdominal injection of fresh, warm blood from a tuberculous cow 
can not protect against tubercle bacilli simultaneously introduced 
into the abdominal cavity : group 3, to show that the intraabdominal 
injection of fresh, warm blood from a tuberculous cow can not pro- 
tect against tubercle bacilli introduced into other parts of the body 
than the abdominal cavity ; groups 4 and 5, to show that the blood of 



SUPPLEMENTAL TESTS REGARDING IMMUNITY. 21 

tuberculous cows has no special germicidal potency for tubercle 
bacilli ; groups G and 7, to serve as guides relative to the amount of 
tuberculous disease to be expected in the bodies of the guinea pigs 
that were injected Avith both blood and emulsion of tul^erculous 
material. 

(iUOUP 1. 

On April 24, 1909, eight guinea pigs, Nos. 3626 to 3633, inclusive, received 
each :in intraabdominal injection of 3 c. c. of freshly drawn warm blood. On 
May (■>, 1909, guinea pig 3627 died affected with congestion of the lungs. On 
autopsy no lesions of tuberculosis were found. On May 27 and 28, 1909, guinea 
pigs 3626, 362S, 3620, 3(530, 3(!31. 3632. and 3633 wero killed and examined post- 
mortem. No lesions of tuberculosis or other disease were found. 

GUOUP 2. 

On April 24, 1909, eight guinea pigs, Nos. 3642 to 3649, inclusive, received 
each an intraabdominal injection of 3 c. c. of freshly drawn blood, followed 
as quickly as possible by an intraabdominal injection of 0..") c. c. of tuberculous 
emulsion. On April 30, 1909, guinea pig 3642 died affected with inflammation 
of the large bowel. On May 27, 1909, guinea pigs 3643, .3644. 3645, 3646, 3647, 
3648, and 3649 were killed and examined post-mortem. Every one of the seven 
was found to be affected with generalized tuberculosis of the abdominal and 

thoracic organs. 

GROUP :!. 

On April 24, 1909, eight guinea pigs, Nos. 3634 to 3641, inclusive, received each 
an intraabdominal injection of freshly drawn warm blood, followed as soon as 
possible by a subcutaneous injection into the right thigh of 0.5 c. c. of tuber- 
culous emulsion. On ]\Iay 27, 1909, guinea pigs 3636 and 3637 and on May 28, 
1909, guinea pigs 36.34, 3635, 3638, 3639, 3640, and 3641 w^ere killed and examined 
post-mortem. The eight guinea pigs all showed more or less extensive lesions 
of tuberculosis at the seat of the subcutaneous injection, tuberculosis of the 
adjacent superficial inguinal gland, tuberculosis of the pelvic, lumbar, and 
gastro-hepatic glands, and a sprinkling of tuberculous foci in the liver and 

spleen. 

GROUP 4. 

On April 24, 1909, eight guinea pigs, Nos. 36.58 to 3665, inclusive, received each 
an intraabdominal injection of 3 c. c. of a mixture of defibrinated blood and 
tuberculous emulsion. Each 3 c. c. of this mixture was equivalent to 0.5 c. c 
of the diluted tuberculous emulsion described earlier. The mixture was two 
hours old at the time it was injected into the guinea pigs. On April 25, 1909, 
guinea pigs 3659, 3660, :tnd 3661 died. The post-mortem examinations showed 
no lesions excepting a congested condition of the lungs and a quantity of 
unabsorbed blood in the peritoneal cavity. On May 12, 1909, guinea pig 3662 
died affected with congestion of the lungs; no lesions of tuberculosis were found. 
On May 27, 1909, guinea pigs 3658, 3663, 3664, and 3665 were killed and exam- 
ined post-mortem. Three of them were affected with completely generalized 
tuberculosis of the abdominal and thoracic organs, and the remaining one (No. 
3665) with generalized tuberculosis of the abdominal organs only. 

GROUP 5. 

On April 26, 1909, eight guinea pigs, Nos. 3670 to 3677, inclusive, received 
each an intraabdominal injection of 3 c. c. of the same mixture of blood and 



22 TESTS CONCERNING TUBEECLE BACILLI IN THE BLOOD, 

tuberculous eunilsiou used for the guinea pigs of group 4. The mixture was 
forty-five hours old at the time it was injected. On May 27, 1909, the eight 
guinea pigs were liilled and examined post-mortem. Seven of them were 
affected with generalized tuberculosis of the abdominal and thoracic organs, 
and one (No. 3672)' with generalized tuberculosis of the abdominal organs only. 

GROUP G. 

On April 24, 1909, four guinea pigs, Nos. 3650 to 3653, inclusive, received 
each an intraabdominal injection of 0.5 c. c. of tuberculous emulsion. On 
May 6, 1909, guinea pig 3051 died affected with congestion of the lungs. On 
May 27, 1909, Nos. 3650, 3652, and 3653 were killed and examined post-mortem. 
No. 3650 showed tuberculous lesions of the spleen and omentum only, and Nos. 
3052 and 36.53 showed a faii'ly generalized tuberculosis of the abdominal and 
thoracic oi'gans. 

GROUP 7. 

On April 24, 1909, four guinea pigs, Nos 3654 to 3657, inclusive, received each 
a subcutaneous injection, in the right thigh, of 0.5 c. c. of tuberculous emulsion. 
On May 27, 1909, the four guinea pigs were killed and examined post-mortem. 
Nos. 3654 and 3656 each showed a small tuberculous abscess at the seat of 
injection, a tuberculous condition of the superficial inguinal gland near the 
seat of injection, and a fairly generalized tuberculosis of the pelvic and abdomi- 
nal organs. Guinea pigs 3655 and 3657 showed similar lesions with the excep- 
tion of the abscesses at the seat of injection. 

The autopsy records of the guinea pigs show, in a general way, 
very little difierence between the animals that received only tuber- 
culous emulsion and those that received both blood and emulsion. 
The guinea pigs that received both blood and emulsion into their 
abdominal cavities showed numerically more extensive lesions of 
tuberculosis than the guinea pigs that received only emulsion into 
their abdominal cavities. This condition would naturally be ex- 
pected because the same number of tubercle bacilli contained in 3 
c. c. of blood would be .more widely separated and in better condi- 
tion to start a large number of individual lesions than those in 
0.5 c. c. of salt solution. 

The use of an emulsioif of tuberculous tissue from the tuberculous 
cow that supplied the blood for the supplemental injections was 
preferred to the use of a pure culture of tubercle bacilli, because it 
seemed desirable to us to use infectious material and blood in this 
instance from the same individual case of tuberculosis. 

The total number of guinea pigs injected in this supplemental 
investigation was 48, of which 8 received blood only, 32 both blood 
and tuberculous material, and 8 tuberculous material only. Of the 
32 that received both blood and tuberculous material and the 8 that 
received only tuberculous material, 6 died prematurely, and the 
remaining .34, when they were killed — thirty to thirty-one days after 
the injection — were all found to be aft'ected with tuberculosis of a 
form that would have progressed to death in a short time. 



CONCLUSIONS. 23 

Among the 8 guinea pigs that received an injection of fresh warm 
blood "without the addition of tuberculous material, 1 died prema- 
turely and the remaining 7 were found on autopsy to be free from 
lesions of disease. Since the cow that supj^lied the blood for the 
injections was afl'ected, as her record shows, with extensive, advanced 
tuberculosis, the 7 guinea pigs make a strong addition to the 88 
parallel cases of which the records have been previously given; and 
hence we have 95 guinea pigs as the total number that received injec- 
tions of blood from tuberculous cattle into their peritoneal cavities — • 
the most delicate test for tubercle bacilli available — and survived the 
injection long enough for tuberculosis to manifest itself clearly. 
Among this total of 95 guinea pigs not one case of tuberculosis 
developed." 

CONCLUSIOISrS. 

1. "We failed utterly to find tubercle bacilli in the blood of tuber- 
culous cattle which we examined microscopically in accordance with 
the method described and used by Doctor Rosenberger. 

2. The negative results of our microscopic examinations are con- 
firmed by the negative results obtained with 95 guinea pigs, each of 
which received an intraabdominal injection of blood from a tuber- 
culous cow or bull. 

3. As the number of cattle from which blood was injected into the 
95 guinea pigs was 42, and as these cattle represented practically all 
stages of tuberculosis from mildly affected recent cases to old and 
completely generalized cases, we feel that our work shows beyond 
the remotest doubt that tuberculosis is not to be classified, in any 
sense of the word, as a bacteriemia. 

"An indepencleut investigation relative to the occnrrence of tnbercle bacilli 
in tbe circnlatiug blood of cattle was made in the Biirean of Animal Industry 
by Dr. John R. Mohler, chief of the Pathological Division. Mohler examined 
the blood of S cattle microscopically, and with blood from each of these cattle 
injected 5 guinea pigs. The microscopic examinations and injections were made 
precisely in the manner described by Doctor Rosenberger. No tubercle bacilli 
were discovered microscopically, and not one of the 40 injected guinea pigs con- 
tracted tuberculosis. Two of the S cattle were in good condition, but were 
jiassing tubercle bacilli from their bowels; 2 of the cattle were in poor con- 
dition and were passing tubercle bacilli from their bowels; and 4 of the cattle 
were slaughtered for meat, but on inspection were found to be so extensively 
affected with tuberculosis that it was necessary to condemn and tank their 
carcasses under the Federal meat-inspection regulations. This evidence, kindly 
presented to us by Doctor INIohler, raises the number of tuberculous cattle from 
which blood was tested to 50, and the number of guinea pigs that received 
injections of blood from tuberculous cattle without contracting tuberculosis 
to 135 

o 



-!!'"'" ""^^SRESS 



002 850 302 tU/ 



